Heat shield having locating and retention features

ABSTRACT

A heat shield assembly includes shroud or housing fabricated from a heat shielding material having at least one pair of spring arms extending from side walls of the shroud for engaging a member to which the heat shield assembly is to be attached, and one or more retention tabs projecting into a longitudinal channel in position to limit longitudinal movement of the assembly relative to the member when the member is attached to the spring arms

This divisional application claims priority to U.S. Utility applicationSer. No. 11/619,736, filed Jan. 4, 2007.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates generally to heat shields and more particularly tosystems and methods for attaching heat shields to a member to beshielded.

2. Description of Related Art

Engines in high performance modern vehicles operate at very hightemperatures. Certain components of the engine are prone to generatingsignificant heat, such as the exhaust manifold and associated exhaustpiping system, the engine block, etc. The excessive heat can be harmfulto some neighboring components if left unprotected. It is common toemploy various heat shields in under-the-hood applications as a means ofshielding such neighboring components from direct exposure to thedamaging heat. Various techniques are employed for attaching the heatshield in a desired position to be effective. One such approach employsspring clips that enable the heat shield to be pushed into engagementwith a member to be shielded. Such spring dips have limitations in that,depending on their configuration, they can be unidirectional so as tosecure the heat shield against removal in the reverse direction ofinstallation, while enabling movement of the heat shield in otherdirections relative to the member to which they are attached.

SUMMARY OF THE INVENTION

A heat shield assembly constructed according to one aspect of theinvention comprises a shroud or housing of heat shielding material, atleast one pair of spring arms extending from side walls of the shroudfor engaging a member to which the heat shield assembly is to beattached, and one or more retention tabs projecting into thelongitudinal channel in position to limit longitudinal movement of theassembly relative to the member when the member is attached to thespring arms. The spring arms are attached to the member in a manner thatpermits the member to slide relative to the shroud in a longitudinaldirection toward an open end of the longitudinal channel. The retentiontabs are arranged to engage the member when it is slid to prevent itfrom sliding out of engagement with the spring arms and/or sliding outthrough the open end of the shroud.

According to a further aspect of the invention, the assembly may alsoinclude an inner frame that supports an outer heat shielding layer andthe retention tab and spring arms may be formed as part of the framestructure.

The invention further contemplates a method of mounting a heat shieldassembly to a member to be shielded that includes preparing the heatshield assembly having a channel-shaped shroud of heat shieldingmaterial with a pair of spring arms provided on side walls thereof andhaving at least one retention tab projecting into the channel, and thenattaching the heat shield assembly to the member by extending the memberinto the longitudinal channel in a direction transverse to alongitudinal direction of the heat shield to engage the spring arms withthe member thereby securing the shield against inadvertent removal inthe reverse direction of installation, while permitting the member toslide relative to the spring arms toward an at least one open end of thechannel, and limiting longitudinal movement of the member relative tothe spring arms by locating the at least one retention tab in the pathof the member to limit longitudinal movement of the member relative tothe spring arms. The retention tabs thus present a barrier to freesliding movement of the member within the channel to prevent the memberfrom sliding out of engagement with the spring arms and/or out of theopen end of the channel.

BRIEF DESCRIPTION OF THE DRAWINGS

Advantages of the present invention will become more readily appreciatedwhen considered in connection with the following detailed descriptionand appended drawings, wherein:

FIG. 1 is a front view from the longitudinal end of a heat shieldassembly attached to a member according to the exemplary embodiment ofthe invention.

FIG. 2 is a plan view of a heat shield assembly according to theexemplary embodiment of the invention.

FIG. 3 is plan view of the inside of a heat shield assembly according tothe exemplary embodiment of the invention.

FIG. 4 is a schematic view of the heat shield assembly according to theexemplary embodiment of the invention.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT

Referring to FIGS. 1 and 2, a heat shield assembly 10 according to apresently preferred embodiment of the invention includes a heat shieldbody or shroud 12, an attachment device 14 carried on the shroud 12 andoperative for releasably securing the heat shield assembly to a member16 to be protected by the heat shield assembly 10, and supplementalretention members 18 carried on the body in spaced relation to theattachment device 14 and operative to locate and selectively engage themember 16 to position and retain the heat shield assembly 10 on themember 16 in cooperation with the attachment device 14.

The shroud 12 may include a base 20 and at least two sides 22, 24. Thesides 22, 24 extend from the base 20 in spaced apart relation to oneanother to define a space 26 into which the member 16 can be disposedfor shielding the member 16 from exposure to heat external to the heatshield assembly 10. The heat shield assembly 10 is thus operative tocover and protect the member 16 from exposure to one or more sources ofheat that could otherwise act to harm the member 16. For example, theheat shield assembly 10 can serve to reflect radiant heat and/or blockthe transfer of conductive heat to the member 16.

The shroud 12 in the illustrated embodiment is generally channel-shaped,with the base 20 forming a base wall of the channel and the two sides22, 24 forming the side walls of the channel. Opposite longitudinal ends28, 30 of the shroud 12 may be open to the space 26 such that the shroud12 is generally U-shaped when viewed from a longitudinal end of the heatshield assembly 10.

The shroud 12 may be made of any of a number of heat shielding materialsthat would be effective to shield the member 16 from heat and may berigid or flexible. One suitable construction includes a multilayer heatshielding material 31 having a substantially nonconductive insulatinglayer 32 of nonwoven polyester felt or glass fiber mat sandwichedbetween outer and inner layers 34, 36 of a reflective metal foil such asaluminum. This multilayer heat shielding material 31 may further includea relatively rigid inner support frame 38 about which the multilayerheat shielding material 31 may be draped to impart a self-supportingshape to the shroud 12. In the illustrated embodiment, the frame 38 hasa generally U-shaped channel configuration and the multilayer heatshielding material 31 may be permanently secured to the frame 38 by anysuitable means, such as rivets 40 in the base 20 of the shroud 12. Thematerial 31 could also be secured to the frame 38 by a suitable adhesiveor other mechanical fastening means.

Referring to FIGS. 2 and 3, the frame 38 operates in the illustratedembodiment to give the desired shape to the shroud 12. The frame 38 mayalso include attachment device features 14 as well as the retentionmembers 18. The attachment device features may comprise snap-lockconnectors that operate to secure the heat shield assembly 10 to themember 16 in response to forcing the assembly 10 into assembledengagement with the member 16. The snap-lock connectors include a pairof opposing resilient spring arms 42, 44 carried on the sides 22, 24 ofthe shroud 12. The spring arms 42, 44 are preferably formed as part ofthe frame 38 and may best be formed by shaping and bending side wallportions 46, 48 of the frame 38 into the shape of the spring arms 42,44. For this purpose, the frame 38 may be made in part or entirely of asuitably resilient material such as spring steel or the like. Suitableplastics materials are also contemplated by the invention. Asillustrated, the spring arms 42, 44 extend in the same direction from abase 50 of the frame 38 toward free ends 52 on laterally opposite sidesof the shroud 12. The arms 42, 44 are spaced from one another and may beinwardly contoured, such as by bending the material, adjacent their freeends 52 to form narrowed catch portions 54 of the arms 42, 44. Thesecatch portions 54 engage the body of the member 16, which may comprise,for example, an electronic sensor. The arms 42, 44 may further extendwidth-wise in the longitudinal direction of the shroud 12 toward theopen ends 28, 30 of the shroud 12.

The base 50 of the frame 38 may carry the retention members 18. Theretention members 18 may project from the base 50 inwardly of the space26 in the general direction of the free ends 52 of the spring arms 42,44. The retention members may comprise two or more tab portions 56 thatare spaced from one another in the longitudinal direction of the shroud12. The spacing of the tab portions 56 is sufficient to accommodate aportion of the member 16 when the member 16 is positioned in the space26 of the shroud 16 to thereby positively locate the member 16 relativethe shroud 12. The tab portions 56 are spaced longitudinally from theopen ends 28, 30 of the shroud 12 and are provided to limit thelongitudinal movement of the member 16 within the space 26 to within theregion defined between the tab portions 56, The tab portions 56 may beformed integrally with the frame 38 by cutting U-shaped slots in thebase 50 and then bending the resultant tab portions 56 out of the planeof the base 50 so that they project into the space 26 in generallyparallel relation to one another.

In operation, the member 16, such as a sensor, is protected fromexposure to heat by positioning the heat shield assembly 10 over themember 16 and then guiding the assembly with force causing the arms 42,44 to widen and push through the catch portions 54 of the spring arms42, 44 as they deflect outwardly. The member 16 is guided into positionpast the catch portions 54 which return inwardly to capture the member16 against removal in the installation direction. The member 16 isfurther captured between the retention tabs 56. In this way, the springarms secure the heat shield assembly 10 releasably on the member in thedirection of installation, while the retention tabs 56 contain themember 16 from moving out of the channel through the open ends 28, 30 ofthe shroud 12. Of course, the retention tabs 56 could also be used inconjunction with a shroud whose ends were not open (e.g., ends which maybe covered by additional sides of the shroud such as a three or foursided shroud). In such case, the tab portions would nonetheless operateto limit the movement of the member 16 in the longitudinal direction ofthe shroud 12 and keep the member 16 positioned in engagement with thespring arms 42, 44.

Many modifications and variations of the present invention are possiblein light of the above teachings. It is, therefore, to be understood thatwithin the scope of the appended claims, the invention may be practicedotherwise than as specifically described.

1. A method of attaching to a member a channel shaped heat shieldassembly having a base, a pair of side walls, at least one open end, anda pair of spring arms, comprising: attaching said heat shield assemblyto the member by extending the member into said channel in a directiontransverse to a longitudinal direction of said heat shield assembly toengage said spring arms with the member against inadvertent removal in areverse direction while the member is able to slide relative to saidspring arms toward said at least one open end; and providing at leastone retention tab projecting into said channel in position to limitlongitudinal movement of the member relative to said spring arms.
 2. Themethod of claim I further comprising providing two retention tabs insaid channel in position to limit longitudinal movement of the memberrelative to said spring arms.